X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Falloca.c;h=3a1f4e273a56b8f4f65e39c35577a1826343de24;hb=4f9d80b9d8004f0fcedf3525e268abaa24b8b4a9;hp=10e5d65f01945193ae63b532c60a39278654c514;hpb=f629cb35ff2a467084745d8e635e41eb1f39f6d8;p=gnulib.git

diff --git a/lib/alloca.c b/lib/alloca.c
index 10e5d65f0..3a1f4e273 100644
--- a/lib/alloca.c
+++ b/lib/alloca.c
@@ -21,12 +21,22 @@
    allocating any.  It is a good idea to use alloca(0) in
    your main control loop, etc. to force garbage collection.  */
 
-#ifdef HAVE_CONFIG_H
-# include <config.h>
-#endif
+#include <config.h>
+
+#include <alloca.h>
+
+#include <string.h>
+#include <stdlib.h>
 
 #ifdef emacs
+# include "lisp.h"
 # include "blockinput.h"
+# ifdef EMACS_FREE
+#  undef free
+#  define free EMACS_FREE
+# endif
+#else
+# define memory_full() abort ()
 #endif
 
 /* If compiling with GCC 2, this file's not needed.  */
@@ -46,6 +56,8 @@
 you
 lose
 -- must know STACK_DIRECTION at compile-time
+/* Using #error here is not wise since this file should work for
+   old and obscure compilers.  */
 #    endif /* STACK_DIRECTION undefined */
 #   endif /* static */
 #  endif /* emacs */
@@ -60,31 +72,6 @@ long i00afunc ();
 #   define ADDRESS_FUNCTION(arg) &(arg)
 #  endif
 
-#  if __STDC__
-typedef void *pointer;
-#  else
-typedef char *pointer;
-#  endif
-
-#  ifndef NULL
-#   define NULL 0
-#  endif
-
-/* Different portions of Emacs need to call different versions of
-   malloc.  The Emacs executable needs alloca to call xmalloc, because
-   ordinary malloc isn't protected from input signals.  On the other
-   hand, the utilities in lib-src need alloca to call malloc; some of
-   them are very simple, and don't have an xmalloc routine.
-
-   Non-Emacs programs expect this to call xmalloc.
-
-   Callers below should use malloc.  */
-
-#  ifndef emacs
-#   define malloc xmalloc
-#  endif
-extern pointer malloc ();
-
 /* Define STACK_DIRECTION if you know the direction of stack
    growth for your system; otherwise it will be automatically
    deduced at run-time.
@@ -107,7 +94,7 @@ static int stack_dir;		/* 1 or -1 once known.  */
 #   define STACK_DIR	stack_dir
 
 static void
-find_stack_direction ()
+find_stack_direction (void)
 {
   static char *addr = NULL;	/* Address of first `dummy', once known.  */
   auto char dummy;		/* To get stack address.  */
@@ -160,9 +147,8 @@ static header *last_alloca_header = NULL;	/* -> last alloca header.  */
    caller, but that method cannot be made to work for some
    implementations of C, for example under Gould's UTX/32.  */
 
-pointer
-alloca (size)
-     unsigned size;
+void *
+alloca (size_t size)
 {
   auto char probe;		/* Probes stack depth: */
   register char *depth = ADDRESS_FUNCTION (probe);
@@ -188,7 +174,7 @@ alloca (size)
 	{
 	  register header *np = hp->h.next;
 
-	  free ((pointer) hp);	/* Collect garbage.  */
+	  free (hp);		/* Collect garbage.  */
 
 	  hp = np;		/* -> next header.  */
 	}
@@ -208,17 +194,26 @@ alloca (size)
   /* Allocate combined header + user data storage.  */
 
   {
-    register pointer new = malloc (sizeof (header) + size);
     /* Address of header.  */
+    register header *new;
+
+    size_t combined_size = sizeof (header) + size;
+    if (combined_size < sizeof (header))
+      memory_full ();
+
+    new = malloc (combined_size);
+
+    if (! new)
+      memory_full ();
 
-    ((header *) new)->h.next = last_alloca_header;
-    ((header *) new)->h.deep = depth;
+    new->h.next = last_alloca_header;
+    new->h.deep = depth;
 
-    last_alloca_header = (header *) new;
+    last_alloca_header = new;
 
     /* User storage begins just after header.  */
 
-    return (pointer) ((char *) new + sizeof (header));
+    return (void *) (new + 1);
   }
 }